These include pro-inflammatory cytokines in septic patients impairing PTH responsiveness,[8–10] catecholamine excess in sick patients, end-organ resistance to PTH, inhibition of PTH secretion and intra- and extracellular redistribution of calcium ion.[11] Hypocalcemia has been reported frequently in ICU setting.[1, 2] The question remains open that whether this represents a marker of disease severity or a direct predictor of worse outcome. This evidence concerns the gene PTH and Hypocalcemia.